American Football - NFL - Kansas City Chiefs Press Conference - Corinthians Arena, Sao Paulo, Brazil - September 4, 2025 Kansas City Chiefs' Travis Kelce during the press conference REUTERS/Jean Carniel
People ride a roller coaster at Six Flags Magic Mountain amusement park in Valencia, California, U.S., April 1, 2021. REUTERS/Lucy Nicholson

By Svea Herbst-Bayliss

NEW YORK (Reuters) -Activist investor Jana Partners has teamed up with football star Travis Kelce to push Six Flags Entertainment to improve its marketing and customer experiences, the investor said, after disclosing a 9% stake in the company.

Jana Partners' Scott Ostfeld announced the position at the 13D Monitor Active Passive-Investment Summit in New York on Tuesday, saying he has partnered with Kelce and two business industry executives to pressure the company to improve its performance.

Shares of Six Flags shot up 17% on Tuesday after Ostfeld spoke to $25.63. The stock is down 58% since it completed a merger with fellow theme park operator Cedar Fair in July 2024.

The stock has a market capitalization of roughly $2.6 billion, and has struggled this year as rainy weather at the start of the summer kept visitors away from its parks.

Kelce, a star tight end for the NFL’s Kansas City Chiefs, is a popular podcast host who recently became engaged to singer Taylor Swift. He has described himself as a theme park "superfan" and has often visited the company's parks.

Jana is joining a field of activists approaching Six Flags with ideas on how to improve the share price.

On Friday, the company said it added an executive from activist hedge fund Sachem Head Capital Management to its board.

Consumer executive Glenn Murphy and technology executive Dave Habiger are also working with Jana and could, along with Kelce, serve as potential board nominees.

(Reporting by Svea Herbst-Bayliss)